Littlefinger tried to spook Bran (or maybe just gain his favor?) by giving him the Valyrian steel dagger used by a would-be assassin who tried to kill him back on the first season. We'll get to the importance of this blade later, but first we must look at the way Bran rattled Littlefinger.

The "chaos is a ladder" callback

"To go through all of that and make your way home again only to find so much chaos in the world," Littlefinger said. " I can only imagine —"

"Chaos is a ladder," Bran said, interrupting.

Bran gave Littlefinger his best spooky stare. HBO

Littlefinger isn't easily unnerved, but you could tell this got to him. "Chaos is a ladder" was the iconic line from a speech he gave to Varys back on the third season. Varys confronted Littlefinger in the throne room about his scheming and Littlefinger got very real about the way he's played the game of thrones.

"Chaos isn't a pit. Chaos is a ladder," he told Varys. "Many who try to climb it fail, and never get to try again — the fall breaks them. And some are given a chance to climb, but they refuse. They cling to the realm, or the gods, or love ... illusions. Only the ladder is real, the climb is all there is."

It's also noteworthy that this speech touches on "falls that break" people, just like Bran. HBO

Bran repeating this line back to him was a signal that Bran has used his greensight to trace Littlefinger's movements in the past. It also means Bran probably knows who hired an assassin to come after him with that Valyrian steel blade, even if Littlefinger is trying to play dumb.

Who really sent the assassin and why it matters for Littlefinger

Bran asked Littlefinger if he knew who the Valyrian blade belonged to and Littlefinger says he doesn't. Littlefinger also acknowledges that that question sparked the War of the Five Kings. Catelyn Stark brought the dagger to King's Landing, where she asked Varys and Littlefinger what they knew of it.

Littlefinger told Catelyn the blade had once been his, but he lost it in a bet to Tyrion Lannister.

Littlefinger lied about Tyrion owning the dagger. Was that just to cause chaos? HBO

This lead Catelyn to arrest Tyrion when she ran into him at an inn on the Kingsroad, and that capture lead Jaime to attack Ned and his men in King's Landing. Then Tywin Lannister went to war over the imprisonment of Tyrion, because he was worried about the Lannisters' reputation.

But at this point, we all know Tyrion wasn't the one who owned that dagger and sent a killer after Bran. Tyrion was the one Lannister who had no ill will against any of the Starks, and he would never have bet against his brother Jaime in the first place (which was how Littlefinger claims his lost the dagger).

So who was its owner? Was it Littlefinger?

In the books, the assassin was likely hired by Joffrey

In the books, Jaime remembers King Robert Baratheon displaying the Valyrian steel dagger at a feast after a tournament. We also learn that both Tyrion and Jaime believe Joffrey was the one who sent the assassin after Bran.

Joffrey may have wanted to impress his father. Google Images

They agree that he likely did it in a weird, backwards attempt to please his "father." Joffrey overheard King Robert saying it would be a mercy to kill Bran rather than let him be crippled, and so Joffrey likely took the blade from the royal carriage and hired a cutthroat.

But is the show changing this storyline and making Littlefinger the owner?

If Bran uses his greensight, surely he'll be able to see who gave the Valyrian blade to a cutthroat. Perhaps this will be one more mar on Littlefinger's reputation with the Starks. Sansa already knows how he betrayed her by handing her off to the Boltons without properly understanding Ramsay's sadism.

Arya has reason to distrust Littlefinger because she saw him conspiring with Tywin Lannister when she was serving as his cupbearer in Harrenhall.

Littlefinger visited Harrenhall when Arya was there. HBO

And now Bran knows about Littlefinger's true motivations, and likely has seen the moment when Littlefinger betrayed Ned Stark — leading to his execution.

Why Arya owning the dagger now has a larger meaning

Bran has been really off-kilter since he traveled south of the Wall. He doesn't consider himself to be Bran Stark anymore, but instead he's the Three-Eyed Raven. This means most of his interactions with everyone have been stilted and without emotion.

That's why I was surprised to see him pull out the Valyrian dagger, unprompted, when he was with Arya and Sansa. It's not as if one of them asked about it first. So why did he feel the need to bring it up and hand it over to Arya?

Bran likely gave Arya the blade for a reason, but we'll have to wait to see what it is. HBO

Bran's greensight works with seeing the future, too. One of his crazy vision montages on the sixth season showed Cersei blowing up the sept with wildfire before it happened.

Has he seen Arya using the Valyrian dagger, and knows she's meant to wield it? Valyrian steel is one of the few substances that we know can kill a White Walker. When the real war begins, Arya will surely be among the living as they fight the dead.

Fingers crossed we see Arya take on a White Walker in even more badass fashion than her first training spar with Brienne of Tarth.